update serde

[arvidn]

This fixes a build error in the fuzzers.

error[E0658]: `#[diagnostic]` attribute name space is experimental
   --> /Users/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/serde-1.0.204/src/de/mod.rs:537:5
    |
537 |     diagnostic::on_unimplemented(
    |     ^^^^^^^^^^
    |
    = note: see issue #111996 <https://github.com/rust-lang/rust/issues/111996> for more information
    = help: add `#![feature(diagnostic_namespace)]` to the crate attributes to enable
    = note: this compiler was built on 2024-02-10; consider upgrading it if it is out of date

[coveralls-official[bot]]

Pull Request Test Coverage Report for Build 9864743787

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.02%) to 94.162%

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Totals
Change from base Build 9836005106:	0.02%
Covered Lines:	5806
Relevant Lines:	6166

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💛 - Coveralls